An advert appeared in 1900 for the cloth and carpet business known as "Julius Sussmann formerly L. Borinski" trading at the same address as Samuel Borinski's former business in Krolewska Huta; thus it appears that Leo inherited his father's premises and probably his business, but had himself been succeeded by 1900.

Katolik, 1900, R. 33, nr 53 page 6

He was living in Berlin and described as a businessmann when he married in 1897 and he appeared in the Berlin address books from 1897 onwards. In 1914, when he reported the death of his mother-in-law, he was described as a factory owner. There is strong circumstantial evidence (see Rudolf Hugo Moos: Journey of Hope and Despair) that Leo took over Emil Pinner's shoe factory in 1902-1903 after several years as a leather trader in Berlin. According to Moos, Leo's son Werner was also involved in the shoe factory.

Leather trading ran in the family: the 1892, 1902 and 1914 Upper Silesia business directories list a Max Borinski as owner of A. Borinski kolonialwaren and leather merchant in Sohrau. It is very likely that this firm started with Adolf (Josef) Borinski, since a Josef Borinski is mentioned in Geshichte der Stadt Sohrau in O-S as a Sohrau merchant trading in spice and cloth in 1840. It is likely that the business thrived and passed to his son Adolf (Jacob) Borinski, especially as Adolf (Jacob) Borinski's two eldest sons, Louis and Samuel (Leo's father) went on to own kolonialwaren businesses in their own rights.